1. Field of the Invention
This invention pertains to electrical power sources, and more particularly to electrical power sources for mobile storage carriages.
2. Description of the Prior Art
Mobile storage systems have gained widespread acceptance in libraries and offices because of their ability to save valuable floor space. Electrically powered mobile storage systems are becoming increasingly popular to move heavily loaded carriages without expending muscular effort.
A potential disadvantage of electrically powered carriages is the possibility of line power failure. In addition, a component of the mobile storage system electrical control or safety stop systems conceivably may fail. In either event, a carriage cannot be moved under power until the failure is corrected.
Although mechanical overrides are available, they are not suitable for use with all movable carriages. For example, mechanical overrides cannot be used on carriages that are not equipped with line shaft drives. Even if the carriage is equipped with a suitable mechanical override, manual force is required to move the carriage.
Another possible shortcoming of electrically powered mobile storage systems is the inability to move the carriages during assembly of the shelves before the control system has been installed. Manual movement of partially assembled carriages is inconvenient and reduces manufacturing productivity.
Thus, a need exists for a universal source of power for moving electrically powered mobile storage carriages under abnormal operating conditions.